The study found that this is attributable to an "oral sex gap," where "Men receive oral sex about 80% of the time in first-time hookups, whereas women receive it less than half the time."

They also found that the "oral sex gap" narrows as casual sex becomes something more serious, because men are less likely to care about their partner's pleasure when it's a casual hook-up. The same doesn't apply to women, who perform oral sex 80% of the time even when it's a first time hook-up.

This inequality, which is really a form of "sexual injustice," can be explained by how men and women are socialized in a sexist society where magazines targeted at women focus on "101 ways to please your man" while magazines targeted at men feature pictures of scantily-clad women talking about how much they love to please their man.

Because of sexism, women are treated as second-class citizens, oppressed and valued less than men, and sex is no different: as private as it is, sex takes place within the context of an oppressive society. In fact, because gender and sexuality form a basis for oppression, sex is often a place where these injustices manifest themselves more acutely.

I'm struck by your choice of referring to making sure one's partner gets off as a "courtesy/nice gesture," which really illustrates the problem.

In a capitalist society where sex is a commodity and the female body is objectified and therefore "consumable," heterosexual men are socialized to view sex as a thing, something they get from women, rather than a relation between two people.

This manifests itself in the words we use. Men "get some," while women are warned against "giving it away too easily."

Poly Amory addresses this well on her blog "My Life as a Serial Dater." She counters the saying "he's not going to buy the cow if he gets the milk for free" with:

"I am not a "cow." My vagina is not "milk." And who said anything about "free." Nothing about me is for sale or give-away. I am a person, not a commodity."

This leads into the other part of the problem. While men are encouraged to view sex as a thing they try to get, and are celebrated for their "conquests," women are socialized to guard and repress their sexuality lest they be perceived as "easy." A woman comfortable with her sexuality and sexual appetite, needs, and desires, faces stigma, demonization, and abuse.

Given the stigma attached to gay sex, the ideal of the promiscuous man and the chaste woman presents a contradiction, one that is resolved by dividing women into two categories, both of which are oppressive, both of which define women as property. She is either a potential wife, to be placed on a pedestal where her sexuality is restricted or denied through enforced monogamy, or she is to be used as a sex object, to be used and then discarded.

As Karl Marx's collaborator Frederick Engels wrote in The Origin of the Family, Private Property, and the State, "monogamy and prostitution are indeed contradictions, but inseparable contradictions, poles of the same state of society."

This is not to say that all men think like this, only that this is the sexist ideological and material context in which heterosexual sex takes place. It's possible that a man might idealize you, and have difficulty comprehending that you are a sexual being with needs and desires, or that he sees you as a sex object, and is concerned with getting what he wants, regardless of whether or not you get what you want.

If he operates on either of these bases, he'll likely be unresponsive if you tell him what you want, and in that case my advice would be to move on, as there are people out there who will take your pleasure into account (my roommate assures me from the couch that he is one of them).

Any man worth having sex with should make a serious effort to make sure that you, and not just him, have an orgasm (at least) and beyond that have a comfortable, fulfilling experience. Assuming he does want you to feel good, have an orgasm (or better yet multiple orgasms), communication is definitely the key.

But I would recommend treading lightly until you know what the issue is. (If you and your partner do have successful open communication about sex, then by all means be blunt, but I'm assuming there are communication issues if you aren't getting off.)

Given the general lack of communication and knowledge about sex, a product of a society where "abstinence only" sex-education is all too common, it's likely that your partner may want to please you but doesn't know how, which is embarrassing.

It's also possible that he would like to last longer, but he has trouble holding off, another source of shame.

Or, he might assume that you've come already, mistaking your moans of pleasure as you build toward an orgasm for your orgasm itself.

So before you tell him that you aren't satisfied, try addressing the issue with positive solutions, by showing him how to please you, telling him what gets you off, and showing him how to do it. Teach him about your body, how to read your signals, and make sure that you are sending them.

You can masturbate in front of him, so he can see how you touch yourself, what makes you feel good. Have him place his hand over yours, or guide him while he touches you. Tell him what feels good, so he can learn your body language and know when he's doing something right. And ask him to make sure you are turned on and well on your way before you move on to intercourse, whether that's from oral sex, manual stimulation, or whatever else turns you on.

Try telling him when you come, and tell him beforehand that you will tell him when you come. If you're having intercourse and you think he's getting close but you're a ways off, slow down or stop. You can pull him out, squeeze his penis (not too hard!) below the head and rub it against your clit, bringing you closer while slowing him down and preventing ejaculation.

Tell him to pull out and go down on you, then pull him back up and put him back inside of you. Mix it up, try different things. Be creative.

If you try these things and he still leaves you unsatisfied, tell him that you're unsatisfied and that if he wants to keep having sex with you he's going to have to start making sure that your needs are met.

Good sex requires that both partners are aware of what the other desires and whether or not they're getting it, and that they do what they can to please one another. If your partner respects you, he will respond. If not, he's not worth the time or frustration.

Finally, a major source of sexual frustration is the notion of sex having to stick to some sort of routine, like: kissing, then oral (maybe), then intercourse, then the woman comes (hopefully), then he comes, then you clean up and part ways/fall asleep.

A lot of women enjoy intercourse but can't have an orgasm from it most of the time or ever, and there will be times when men, despite their best efforts, will be unable to hold off and will come before you.

Just because a man comes doesn't mean he can't continue to stimulate you with his fingers, tongue, a vibrator, etc, until you have an orgasm as well. Men shouldn't take their orgasm to mean it's polite to roll over and go to sleep if their partner isn't satisfied, nor should women feel it's out of line to ask their partner to continue to stimulate them after he's come.

ADDENDUM

Shortly after I published this, I received the following message:

While I appreciate the effort & thought you are putting into this, I am curious as to why you are addressing your suggestions and instructions only to women. Yes, open communication and dialogue are certainly important in any relationship which ranges from the purely physical to long-term partnership, but you seem to project the idea that is up to women - rather than men - to do the work in handling this particularly intimate form of sexism, and as well-meaning as I realize this post is, I think it at least partially perpetuates a patriarchal and sexist discourse which leaves it up to women to educate men, instead of challenging men to take it up themselves.
Rather than providing advice to women on how to better communicate, perhaps this space might be better utilized in calling on (other) men to reconsider their 'bedroom politics' and take a critical look at how their behavior reinforces the sexism embedded in our social structure.

To be clear, it wasn't my intention to imply that the solution to the "orgasm gap" entails women communicating better, nor do I think it's up to women to change sexist and inconsiderate men so that they care about getting their partner off. I wrote above that I don't think that men who aren't interested in making an effort to please their partner are worth wasting time on.

That isn't to say that those men won't ever change, but someone so sexist that he doesn't care if the woman he happens to be sleeping with is enjoying herself is unlikely to be changed by better communication, nor is it a woman's responsibility to do so.

My advice was intended for the woman asking the question, with the goal of providing some incite on how to help a (relatively) clueless partner, who does want to please her, be a better lover, in a way that I believe will be useful in her getting more of what she wants out of sex (orgasms).

While the individual men whose bad ideas and behavior around sex comprise the problem of the "orgasm gap" should take the responsibility to critically examine the way they view women and make every effort to change, I think that it is going to take a revival of the women's liberation movement to force that change in a meaningful way.

And solving it once and for all is only possible with a fundamental, revolutionary change in our society.